Raw Transcript
So, this video is on critical points and critical numbers, with regard to graphing by hand in calculus. Calculus one, or all through calculus I guess. Ahh Let’s get started. You press second alpha on your calculator titanium. See this box here which turns black which shows you that you can enter letters. And the code for my menu of course is I n d e x, and then you have to press alpha to get back to numbers and parenthesis, and you’re into my menu. My menu has many many things in it. Right now we’re talking about critical points, so – were gonna go – uhm – to critical points. Pull up the program, and I tell you to mark on your paper right away, on your test paper or whatever, ya know, a graph with these, ahh all labeled in numbers so you can mark down whatever comes up in my program, and then you can, ya know, connect the dots and have your graph completed – by hand. So we’re going to enter a function, a from a test, we’re going to have to – for any of these boxes that come up in my programs you have to add alpha – you have to press alpha first – so we press alpha, and we’re going to put in x cubed minus six times x squared, plus nine times x and plus two, and then press enter twice – and I show you what you’ve entered, in case you want, made a mistake, you can go back and do it, you press enter again, you can, ok or change it – I’m saying its ok – my programs also, you can press the number before these what the choice is, you can scroll down, or and then press enter, but you can also just press the number and it will go right to there. So were at critical points, we want critical points in the menu, instead of scrolling we’re going to just press three on the calculator – and – and I – discuss a critical points and numbers in a blog in my web site, so check that out. Most tests, come up with, ask you for critical points, and there’s a difference between critical numbers, critical points – and I discuss that – here I put a little bit of information about it. Critical point is really an xy point on the graph, and critical numbers are – are on the x axis, just what the x value is – however – professors and tests I’ve seen – uhm – ah – you know use both and – and it’s not correct, their different. Ahh, So – in critical numbers, your gonna – you’re going to set the uhm, first derivative to zero, and then solve for x – so we factor the first derivative, here, and we come up with the critical numbers – x equals three or x equals one – that’s what you’d put down – You put everything on your test, just like this. You can’t find the first derivative unless you put the function down – then you find the first derivative – and go from there – uhm – I do the – I find critical numbers and critical points on my programs – so – we add – we take three – one of the critical numbers of three – and plug it into the first function – three cubed, times, minus – six times three squared, plus nine times three, and you write this on your paper and you come with two – y equals two – so the first critical point is three and two – second one you plug in one for critical number into the primary function, and come up with six – so the second critical point is one and six – and then, it takes you back – you can find more parameters here, press one, you can get more parameters, and go whatever you want – local maximum min – Intervals of increase decrease – inflection point – what ever you need to complete the graph
Joe Meyer says
Tommy,
Great talking with you last night. I already liked you for developing this “most excellent program” but after our conversation I concluded you to be a great guy. I’ve been playing with this program most of the night, took in a few “z’s” and am back for more. This program really is superb. I did, however, notice that for some unknown reason when I attempt to do Relative Extrema’s and Trajectories that both programs came up as “Program not Found”. I’m not sure if I will be encountering the Trajectory stuff in this semester of Calculus but I do have a test this Thursday that includes Relative Extrema. Any suggestion, oh Master of this great creation?!
I’m going to be gone most the day but should be home late afternoon if you got time to call. Same number (843-xxx-xxxx). That’s Myrtle Beach, 3 hours ahead of you and more golf courses than you can shake a stick at.
Thanks,
Joe
VerEty says
(Paperback) This book, of which I studied the first four cphaters for an independent study course (I’m a senior undergrad) are very clear, very full, but beware it is mathematics and it is technical.To appriciate the material you really should have a year of advanced calculus also called intro. real analysis at some places. This means the formalities of limits, continuity, derivatives, integration and series. This will prepare you to understand and work through the proofs in the text.The problems are nice since they are varied (computational, physics, and proofs) and they do come with many answers and some hints, but you might find that having a mechanics book at your side motivates some of the problems.Work hard, be thorough and there’s a lot of important ideas in this text, with chapter 4 being especially relevant to physicists (lots of mechanics and conservation theorems!).